Not Applicable.
Not Applicable.
1. Field of Invention
The field of the present invention relates generally to communications and, more particularly, to apparatuses and methods for interrupting certain data transmissions along a communications link while permitting certain other data transmissions along the communications link.
2. Description of the Background
Due to the proliferation of the Internet, the World Wide Web, and web browsers, millions of personal computer users have easy access to a great quantity of information and documents from around the world. Some of the easily available information, however, is not appropriate for certain users. Accordingly, there has been great effort in recent years to restrict the exposure of certain materials to certain users. To address this issue, for example, some governments have legislated censorship of the Internet in order to minimize children""s exposure to pornographic, violent, racist, and other indecent material.
In addition, several non-legislative mechanisms have been proposed and/or implemented to filter the information available to certain Internet users. One such solution includes periodically providing a supervisor (e.g., a parent) with a disk, such as a CD-ROM, on a subscription basis, which contains an updated database of blocked web sites. A utility program cross-references the database of blocked web sites when a user is accessing the World Wide Web, and selectively blocks the loading of the information from the blocked sites identified in the database. A known variation on this solution is to allow the supervisor to create and update the blocked sites, rather than providing them periodically to the supervisor on a subscription basis. These solutions, however, suffer from, among other things, the time delay between the creation of a new, objectionable sites and the inclusion of the sites in the database. They also suffer from the expense associated with monitoring all available sites for content. Furthermore, at least with the periodically provided database of blocked sites, a user is compelled to rely on the judgment of other individuals as to what is inappropriate.
Other mechanisms include generating a user profile including user selected censorship parameters. Data packets routed from a particular site are compared with the profile and, responsive to the comparison, either selectively displayed, modified, or filtered. These solutions, however, suffer from the inflexibility of the profile, as it may cause the filtering of innocuous sites, while permitting the display of sites which, although not within the censorship parameters, are nevertheless potentially objectionable.
A more recent proposal is to provide a coding system, in which organizations or interest groups supply ratings for labeling sites. According to such a solution, browsing software is employed which includes the ability to filter out or block selected sites based on the rating system and/or other criteria, such as viewer age and site content. The drawbacks of the prior mentioned solutions, however, apply equally to such a rating system.
Another solution is to simply prevent all communications between the personal computer and the Internet during certain times, such as time periods of potentially unsupervised usage by children. This approach not only blocks potentially objectionable sites, but all connections to remote data networks are disabled. However, because most personal computer owners/users access remote data networks, such as the Internet, with their personal computer through the same telephone line that connects to their telephone, disabling remote network access may additionally disable their telephone.
Accordingly, there exists a need for a method and apparatus to interrupt data transmissions between a personal computer and remote data networks which is not content-based, yet which does not disable other communications devices connected to the personal computer.
The apparatuses and methods of the present invention provide a practical implementation to interrupt data transmissions along a communications link by monitoring the transmissions for particular frequency patterns, such as those indicative of a modem attempting to establish a connection with a remote data network, such as the Internet. Accordingly, the present invention may be used to selectively restrict access to remote data networks, such as the Internet. The present invention represents an advancement over prior mechanisms because it is not dependent on subjective opinions of the content of the information.
Furthermore, the present invention solves the problem of interrupting data transmissions along a communications link between a personal computer and the remote data network without interrupting the data transmissions of certain other devices using the same communications link, such as a telephone. More specifically, the present invention may interrupt data transmissions only when the modem attempts to establish a connection to a remote data network, leaving other transmissions, such as telephone transmissions, uninterrupted. In addition, the present invention may monitor a voltage level along the communications link and provide a signal indicative of whether the apparatus has been disconnected from the communications link. Thus, the present invention provides the further advantage of deterring tampering, sabotage, or other attempts to bypass or disable the apparatus because such attempts are identified and reported.
The present invention may be programmed such that it prevents remote data network access during certain times of the day, such as when parents are not at home, or it may be activated and deactivated as needed. The apparatus, of course, may be protected by security measures, such as a key or an access code so that only a select group of people can activate or deactivate the apparatus.
An apparatus for interrupting data transmissions along a communications link according to the present invention includes a switch connected in series along a communications link, a filter, and a processor. The filter includes an input terminal connected to the communications link and an output terminal connected to the processor. The processor includes an output terminal connected to a control terminal of the switch. The processor is programmed to detect participation in a handshake operation by a modem connected to the communications link and open the switch when participation in a handshake operation is detected. The processor may detect the modem participating in a handshake operation by the unique frequency patterns employed by modems to establish a connection between a personal computer and a remote data network. Upon detecting participation in the handshake operation, the processor may output a signal to open the switch, thereby interrupting data transmissions along the communications link and preventing a connection with the remote data network. The switch may be closed after a period of time, such as 5-20 seconds, such that other communication devices, such as a telephone, can access the communications link. Because telephone communications do not generate the same frequency patterns as the modem handshake, the operation of a telephone does not cause the apparatus to interrupt the data transmissions along the communications link, thereby allowing telephone use and still preventing modem use.
The switch may be, for example, a mechanical device, such as a relay, or solid state device, such as a transistor. The apparatus may also include a number of output devices, such as light emitting diodes, cathode ray tubes, liquid crystal displays, and audio speakers, to indicate that data transmissions along the communications link have been interrupted and to provide other relevant information. The apparatus may also include an input device, such as a keypad.
In addition to interrupting data transmission between a personal computer and a remote data network such as the Internet, the present invention may be utilized to interrupt data transmissions along a cable TV network to a television.